Dr Chris White, a physicist from the Queen Mary University of London, told MailOnline that string theory "suggests that the basic building blocks of nature, instead of being particles, can instead be strings, planes and higher dimensional generalisations collectively called 'branes'".

"You suddenly wonder if, by any chance, there might be other people living in those branes.

"Could their black holes be a passage between your world and theirs?"

Researchers at the Large Hardon Collider at CERN in Geneva, are looking for tiny black holes as signs of extra dimensions.

A black hole is a place in space where gravity pulls so much that even light can not get out. The gravity is so strong because matter has been squeezed into a tiny space. This can happen when a star is dying.

Worryingly, black holes humanity’s home galaxy could one day be swallowed up by the supermassive black hole that’s lurking at its centre, an astronomy expert has warned.